Anatomy refers to parts of the human body. For example, craniofacial anatomy includes the anatomy of a patient's skull and face, including the dental anatomy of the patient. Dental anatomy includes the anatomy of a patient's mouth, including teeth and soft tissues (e.g., gums). Other examples of anatomy include the bones and other tissues of the thorax, extremities, neck, and other parts of the human body.
Imaging of the anatomy of a patient can be useful to medical professionals, such as physicians and dentists. For example, images of the anatomy may be used to diagnose or treat certain conditions. For some conditions, it is helpful to have three-dimensional images of the anatomy.
For example, dentists often require three-dimensional dental images of the dental anatomy of a patient. One example of a three-dimensional image of dental anatomy is a dental impression. A dental impression captures the shape of at least a portion of a patient's dental anatomy. Typically, a dental impression can also be used to generate a mold of the imaged dental anatomy. This mold can then be used, for example, to fabricate a dental restoration (e.g., a crown, bridge, etc.) for the patient. The mold can also be used for many other purposes, such as planning orthodontic treatment, implant surgery, etc.
Dental impressions are often captured using a physical impressioning material, such as polyvinyl siloxane or alginate materials. These physical impressioning materials are pressed against the dental anatomy, allowed to set, and then removed. Dental images created from physical impressions can suffer from various problems. For example, bubbles can interfere with capturing the dental anatomy. Additionally, the physical impression can distort during removal or over time as the impressioning material dries out or encounters changing environmental conditions. It can also be difficult to duplicate dental images created from physical impressions as the impression is typically distorted or destroyed in the process of making a mold. In addition to capturing dental images, similar techniques can also be used to capture images of other portions of the patient's anatomy, such as an ear canal.
Ultrasound is a sound wave with a frequency greater than the upper limits of human hearing. Ultrasound can be used in medical imaging (e.g., fetal imaging). Typically, in medical imaging applications, sound waves having a frequency in the range of 1 megahertz to 18 megahertz are used.